Collapsible drilling tool



May 8, 19.45. Q 1 WALKER I n 2,375,335

' lCOLLAPSIBLE DRILLING TOOL Filed Sept.'1'7, 1941 3 Sheets-Sheet 1 May 8, 1945.

' c. L. WALKER COLLAPSIBLE DRLLING TOOL Filed sept.l 17, 1941 3 sheets-sheet 2 May 8, 1945. Q L. WALKER 2,375,335

COLLAPSIBLE MILLING TooL Filedvspt. 17; 1941 5 SheB'S-Sheet 3 INVENTOR 'bziw A. 144,2 en

ATTORNEYS.

.are moved into one of the slots.

Patented May 8, 1945A UNITED STATES PATENT' OFFICE I o 2,375,335 f r w COLLAPSIBLE mtiLLING 'rooL Clintonv nwalker, Piedmont, Calif. Application September 17, 1941, Serial No; 411,106

l 10 Claims.

My invention relates to drilling apparatus, and particularly to a drilling tool which is attachable and detachable, to andV from the end of a hollow drill stem. n

The invention relates more' specifically tov the rotary type of drill stem which progressively advances into the bore as it is drilled bythe tool on the end of the stem. `Sections of the drill stem are added as the borev lengthens so that a problem is presented when it vis necessary'to sharpen or renew the tool at the stem end. When the tool is to be withdrawnfthe-stern is raised and section after sectionis removed until the stem is entirely disassembled. When the tool is to be inserted in the bore, the sections arev again assembled seriatim until the tool reaches the bore bottom.

The present 'invention relates to a tool which is attachable and detachable to the end of the v hollow drill stem without the necessity of remov ing the stem from the bore. The invention pertains to a sleeve attached to the end of lthe drill stem which co-operates with the drilling tool to secure the tool in drilling position on lthe stem end from which it may be released and withdrawn through the drill stem. The tool embodies ering cable', is released from the tc'iol'a'n'dthel cable may thereafter be pulled from the drill y stem. A large water passageway is provided raised or lowered in the drill stem. By this arrangement, larger cutting rollers `may be mounted at the end of the stem anda more rigid construction'may thereby be provided.

In the present invention four arms and rollers, one for each of the sides of the mandrel, are provided and additional rollers are mounted on the endof the mandrel to operate on the areain the center of the bore. -Slots are provided in the bottom of the sleeve on vthe stem end for receiving the four arms, and a spiral slot is cut on the cylindrical body of thetoolv in which a spring.. pressed dog projects and rotates the tool at least ninety degrees to locate the roller supporting arms relative to the slots. A stop element limits the downward movement of therindividual arms and causes them to pivot outwardly into a slot inthe end of the sleeve where they are locked in position by the mandrel when all of they arms yWhenthe weight is entirely removed from the tool an overshot, carried by the endof the low- 'tween the drill stem throughthe mandrel from which water is delivered to the bottom fof the bore to-form asludge with the cuttings which is forcedupwardly 4be.-

and the bore wall to the' vtop of the bore.

`A similar tool may be vprovided having the centralmandrel of hollow construction to forni acore-receiving recess with core "cutting rollers provided on the mandrel end for cutting a core as the bore is increased in length. AMeans'ar'e j provided for supporting the core in the toolflso that it may be removed along with the tool from the drill stem. I.

Accordinglythe main objects of `myir'ivention are: to providera sleeve for the end ofa drill` stem anda cooperating tool having pivoted arms whichv extendbeyond the, sleeve after bein'gin-y serted through the hollow drillV stem; `to providey a hollow sleeve for a hollow drillstem whiclfre'- ceives drilling tools which are insertableth'roiigh the hollow stem along with pivotally supported cuttingelements which are swung outwardly and locked on the sleeveendyto provide a tool having a plurality' ofV drilling elements' pivoted on arms suspended one above the other from the end of a mandrelwhichmay be swung seriati'r'nintov place at the end of the drill stem after passing therethrough and locked' inI position. `by themandrel which moves therebetween; to: provide a plurality of drilling elements on the end of a supporting member which is hollow to-form a core passageway having meansV to cut and sup.- 'port a core as well as means toY lock the drilling elements in expanded position at'thel end of: the drill stem; and, in general, to, provide a vtool which is insertable through'ahollow drill stem and whichis locked to the stem end 'without-removing the stem from `the bore, all of Which-is ruggedin construction,A positive in operation. and

economical of use. v

Other objects and features of novelty of' my .inventionwill be either specically pointedY out `or will become apparent `whenreferringffora `all portions of the the tool illustrating' the fluid passageway provided therethrough;

Fig. 7 is an enlarged sectional view of .the structure illustrated in Fig'. 3, taken on the line 1-1.

Fig. 8 is an enlarged sectional view of the structure illustrated in Fig. 4, taken on the line 8 8 thereof;

Y Fig. 9 is an enlarged sectional Vview of the strucc 2,375,335 -tion'ofthe 501 iuustrated in Fig. i Lwith .the

A In Fig. l, I have illustrated the mandrel portion as being in raised position with the lowermost arm 36 in position to be swung outwardly ofthe axis of the sleeve I5. In this position the `v`tool can be raised from the sleeve I5 and the sections of the drill stern; If the tool is to be assembled on the end of the sleeve, further downward movement thereof swings the arm 36 on the segmental bar 32. outwardly into one of the slots I6 throughy the engagement `of the stop pin I8.

with the end of the segmentalbar 32. A further zdownward movement of the mandrel portion 25 moves the arm 36 on the' segmental bar 34 into the opposite slot I6. Thereafter the arm 36 on the segmental bar 33 will be swung into the right yhand slot I6, as viewed in Fig'. l, while further Adownward movement will Ymove the arm 36 on ture illustrated in Fig. 2, Ataken on the line 9- 9 thereof Fig. yl0 is a view yof structure similar to thatA illustrated in Fig. 4, showing a modified form of my invention; and

.Figg 11 is a view of .structure similar to that illustrated in Fig. 4, showing a further form which my invention may assume.

Referring to Figures 1, 2, and 3,-a hollow sleeve i I' I5 is supported on the end of a drill stem `which is made up of aL plurality of .sections of tubing which' is rotated to perform a drilling operation.

which projectsto the bottom of the bore and The sleeve is provided on its ends with a 'plurality of slots I6, herein illustrated as .four in number, disposed 90 degrees apart. Individual stop pins I8 are mounted'on the.v inside wall of `thesleeve I5 a predetermined distance above its lower end. A dog I 9A is mounted near thetop end `of` the sleevefhavinga springwhich urges the doginwardly'of` the inner sleeve wall.r 1

' A-drilling tool 2Ifis illustrated as being suspended within the sleeve I5 onfa cam sleeve 22 having a supporting knob 23.011 the top end. The

cam sleeve ismounted on a'cylindrical element 24 having an outerl diameter. slightly less than the inner diameter of the sleeve I5. A mandrel 25, provided in extension of the tubular portion 24, is square in shape and provided with headed I pins 26 near the lower end. Y

rSlidable segmental bars 3|, 32, 33, and 34, having an outer arcuatesurface tomate with that thesegmental barr3I kinto the opposite slot I6.

The downward movement of all of the arms is terminatedby a pin I8, and the arms are swung outwardly into the positions illustrated vin Figs.

land 4 when the mandrel portion 25 passesdown- Wardly therebetween. f

' The rollers l4I and 42 on the end ofthe man` drel portion 25 in theirlowered position project below the rollers 38. on `the arms 36, as illustrated in Figs. 1 and 4. All of' the rollers arelocked on the end of the sleeve I5 in expanded position with the rollers onrone set of arms extending outwardly a greater amount than the pair` of rollersv on the other arms, as seen in Figures 1 and 44. With the face of the roller v42 on the center line of the sleeve I5, the rollers are in a position to cut all of the material in the bottomof the bore 'as the tool is rotated. The arms 36 on the segmental .bars 3! yand 33 have a slot 44 in the outer wall through which the projecting pins lI8 extend when the arms move through the sleeve.

The upper end of the cylinder portion 241s Y shouldered Ato receive. the cam sleeve 22 and a f locking ring which, asillustrated in Fig. .7,

of the sleeve I5 are of different lengths and are v provided with T-shaped slots 35y which receive thefprojecting headed pins 26. The lsegmentalv bars have arms 36 pivoted on the lower endsv by K 'pins 31. y The ends of the segmental bars and roller supporting arms have a plurality ofmating lands and grooves to reduce the shear strain on `the pins 31. A roller 38 is pivoted in a slot 48 in the end of each arm 36 on apin 39. Rollers 4I and 42 are mounted on the end of the `mandrel portion 25 of the element 24, with one roller of` greater thickness than the other so that one side of the roller 42 may be disposed substantially on the axis of the sleeve I5. A

v The slots I6 are of the same curvature, while the pair of arms illustrated in Fig. 1 are so shaped as to project outwardly a" greater distance than the arms illustrated in Fig.`4 to have the rollers 38 on the respective pairof arms operate in different annular areas. This disposition of' the rollers 38 and rollers 4I and'42assures cutting on areas of'. the 'bottom' of the n bore.

is made up of a plurality of elements 5I secured to an annularspring ring 52 by rivets 53. The elementsl 5I' have a slot 54 Vin their inner faces which receives an' annular projection 55 on the element 24 and prevents relative longitudinal movement therebetween. The-ring 52 retains the elements 5I expanded While maintaining the projection 55 Within the slots 54. The routerwall of the elements 5I are convex in shape to eliminate the possibility of the lower edges of the elements engaging a joint inthedrill stem'and arrest the movement of the tool at that point.

,This eliminates the `possibility ofthe locking ring climbing onto-the tapered surface 56 of the sleeve ,22 during the downward movement of the tool which would wedge the tool within the drill stem.

A threaded collar 60 is screwed uponthe upper end of the'element 24 to limit the upward movement vof the sleeve 22, the head 23 ofV which is engaged by a releasable overshoty support on a Y vcalble by which the tool is raised or' lowered.

When the tool has reached its lowermostposi'- tion, the downward .movement of the mandrel portion 25 is arrested by the locking ring 50 which contacts the lower ledge of an annular vgroove 51 provided in the top portion of the inner When the yoversh'ot is f wall of the sleeve I5. released from the knob' v23 ofthe sleeve 22, the sleeve moves downwardly to cam the ring 50 into 'the slot 51 as illustrated in Fig. '1. This `securely locks the element 24 lagainst upward movement as the drill stem is rotated and moved downwardlyf in the Ibore. 1 C f When the ytool is to be removed, the .overshot is. loweredthrough the' drillsstemzinto, fposition to engage the head 2'3 and'up'ozrbeingv drawnzupwardly, moves the sleeve'22 upwardlyitherewith to release thev lockingringill'whichv permitsy the tool to Ibe moved upwardlyoutof the cylinder I5.

The initialY movement of vthe kelementy24moves the mandrel 'portion 25- frombetween the arms,

36 which swing inwardlyandmove upwardly with the mandrelas thejheadedpins 'Mil thereof engage the segmental bars 3|, 33, 34, andy32 seriatim, to `thereby be suspended belowzthe mandrel portion 35and,each other asfthey are. movedupwardly out of thedrillstem l i When the tool isv lowered `into the sleeve I5,` the. springpressed dog IllY engagesa slot Ell-provided in the Wallofthe cylindrical element 2li forv the so positioned as to drill over all-points` of the area of the bore. A further advantage -resides in the possibility of employing a. large central aperture G3 through the cylindrical element Manda portion of the length of the mandrel portion25. This large opening permits the passage of a large volume'of wateror-mudthrough the-tool'which is pumped down through the drill stem and passes upwardly between the drill stem and the bore wall or casingout ofthetop of the casing. The locking ring 5 0 is also useful irl-sealing .the upper end of the cylindricalportion 2li-relative to the inner wall of thesleeve I5.

In Figure, I :have illustrated `the mandrel portion as havingan end. portion d-which-is preferalbly cast from manganese steel or` other hard alloy.; The end iswelded at 555A tothe end of thev mandrel portion 25 and.- is provided with delivery openingsl 66 and 61 which are disposed, respectively, at 27 and 15 from the horizontal for delivering the iluidkto` the bottom of the b'ore at dilerent inclinations to the toolV axis. The walls of the openings 66 and Elmay lbe surfaced with hardened steel 68 which may be a sleeve welded thereto or which may be a material welded directly to the metal of the casting 54. By having the walls of the delivery apertures 66 and 5l hardened in this -mannerythe wear produced by the passage of mud therethrough is materially reduced.

In Fig. 10, I have showna modified form `of drilling tool wherein a mandrel portion llfof the element 24 is'provided with. a central open` ing 'I0 for receiving a core. .The endfof the elenent 69 carries a pair of core cutting `rollers Il which, as will be seen vfrom the figure, cut a Ycore 'I2 from the bottomoie the bore. A pair of toothed been cut, the tool -of' Figure v10' isi removed. andi the original tool isi replaced onthezstemend. f

y In-Figure l1, I' have illustrated. alfurtherform l ofy my'invention, thatl wherein bladesl Wa-re enr-y ployedi'n. place of thexarms`36.r The pairsjof the blades willprojeot different amountspfrom `the sleeve axis', the same as" the' armsv 43B, `and `the mandrel portiony 15, on the end'vof the elementenY has a cutting portion-'l5 disposedbetweenthe blades. ,This type of tool maybe substituted for the tool .shownin. Figures 1 'to 9,y inclusive, when n ar 'soft-:strata is encountered during the'drilling operation.. `When rock-"or hard'strata is again encountered, thetool having the' blades 1 4 may be removed andthe original toolreplacedt l f Itwill4 be seen that I have` constructed a removablexdrilling tool fora. drill stem which provides a largearea of: Contact' for the bottomfy of the bore. By havingthe arms .and-cutting elementsV supported individually',. one below the otherg. a` stronger and more:ruggedstruCture. is

provided.l The tool is readily removable and. at-

tachable` to the end of thedrillstem and a coring or blade type of tool may be employed when a core isto be cut or'when soft strata-is reached.

AfterV `the bladesor arms have been swungv outward ori-the stem end, they. arewedged outwardly 'by the centraltool portion, the tool andsleeve are `locked together by a locking collar which seals the toolto the sleeve wall. This constructionxof the tool permits the employment of a large=passageway for they wateror` mud; pumped therethrough into they bottom of the-bore'.

WhatIlclair'nis: l Ti l. A drilling tool for'the end oa' drill stem, including in combination, a sleeve,y means for securing said f sleeve tothe end of said'stem; a'

squarci-drilling devicefi insertabler throughsaid stem intozsaidsleeve, segmentallcylindricaldrilling elements pivoted on said device, means for rotating said drilling devicer to havelit' disposed in 'predetermined"relation `to vsaidlsleeve', .means for angularl'y'moving said ydrillingA elementsoutwardly of theaxis of the sleeve different amounts `for covering substantiallythe entire areaolv 'the bottom of the borebeing drilled, means forlocking said Yelements inv drilling-position,` and/means,`

for locking said drilling devicey to said sleeve.l

2. yAfdrilli-ng `tool for the end of a'f'd'rill 4stern including, in combination, a sleeve having slots in its lower end, means for securing the sleeve to the end ofthe stem, a drilling device embodying an upper cylindrical portion and a'lower mandrel portion of square lsection,'segmental cylindrical bars of different lengths supported on said mandrel portion to vform a cylinder therewith, arms pivoted on said bars,v drilling elements on the end of said arms, means for swinging said arms and elements' at an angle outwardly `in a radial direction into the slots in the sleeve asthe drilling devicefis lowered thereinto, and

' an additional drilling element on thejend of theA cam' elements 13 are carried by the mandrel por tion 69 near its lower end for the purposejof engaging and supporting the core l'I2 within the opening 'lll when the tool is raised from the drill stem. When it is desired to obtain a core from the bottom of the bore, the tool as illustrated in Figures 1 to 9, inclusive, is raised from the end of the drill stem and the tool illustrated in Fig.

V10 is substituted therefor, After the core hasmandrel portion positioned between the other of said drilling elements when the mandrel portion wedges the arms in drillingposition.

3. A drilling tool for the end of a drill stein including, in combination, a sleeve having slots in its lower end, means'for securing the sleeve to the end of the stem,a drilling device embodyingk an upper `cylindrical portion and a lower mandrel portion of square section, s'egmentalcylindrical bars of different lengths supported on said square mandrel portion to form a cylinder therewith, arms pivoted on said bars, drilling elements onl the end' of said arms,"means for radialy ly swinging said-arms and elements at an angle outwardlyfinto the slots in the sleeve asithe drill y Ying element'islowered thereinto, an'additional drilling elementen the end of the mandrel por-` tionA positioned between the other of said drilling: elements when the Vmandrel portion wedges the arms rinv drilling position, and additional means for locking the drilling device to the' sleeve near the upper end thereof.: i

vfl'. A drilling tool for the end of a drill stem, al sleeve havingslots on the endrth'ereof, rmeansby which they sleeve is attached to the stem end, 'aiv drilling device havinga cylindrical and a square portion a plurality of armshaving drilling ele-l ments 'on the end thereof,;pivotal means vfor sup- 1 to said sealing member. v .Y f 7. .Adrilling rtool for the end of a drill stem end'by' which said last Vsleeve is movablerelative including, in combination, a 'sleeve secured to said stem, a drillingdevice -insertable into said sleeve having an upper cylindrical portion and a lower square portion',A segmental cylindrical slidable elements on thervfaces of said square por# tion,and cutting elements pivoted to said sliding i elements. f

s, A drilling i001 for the: erifof a ydrin stem including, in combination, a-'sleeve secured to said stemya drilling -device insertable in said sleeve, saiddrilling device, having an `upper cyl [lindrical portion and a lower square portion, seg- `mental cylindrical* slidable elements on said porting the arms one above the other Ion .fthe

square A"end of said device,y means for :swingin'gr said 'arms at an angle into the slots in the: sleeve,;and` additional'drilling elements on the square en d `of thedevice which are centrally disposed krela'tiveto the other of Said elements when the device is positioned between the arms to lock them inextended position;

5, A'vdrilling tool for the end of a drill-stem, a sleeve having slots on the end thereof., .means by which the sleeve'is attached to the stem end, a drilling device having a cylindrical and 'a1 square portion, vsegmental cylindrical members:

square portion, a plurality of arms having drill- 30 ing elements on the end thereof, pivotal means f forl supporting the arms on saidv members vone longitudinally movable on the lfaces rof said above the other on the axis of said'device, means for swinging said arms into the slots in the sleeve,

' the other of saidelemen'ts .when the device is position'ed betweenfthe arms tolock them in extendedfposition, and means vfor lockingA the vdevice tofthe sleeve. f

H y 6. 'A drilling toolVV for the end of ra drill stern l including, in combination, a sleeve secured to f said' stem,v a-drilling deviceinsertable into V,said I sleeve, an lexpansible sealing member carried by 1 f -said fdrilling device byv which said drilling' device-1v is locked tol said sleeve, a sleeve slidable ron said drilling device having a means on one end for exl panding said member, andmeans onthe'opposite y l35 additional drilling elementson the end of the devicewhich are centrally disposedrelative to ported on vprojections and 4forming a cylinder therewith, pivotal arms on said bars swingable radially outward, cutting elements on said arms, and means for retaining said' arms in position at vthe end of the sleeve vwhen themandrel is moved downwardly therein to swing and lock `said arms in cutting position..

10. A drilling Ytool :fory the endy of a drill stem including, in combination, a sleeve 'attachable to the end of kthe stem,v a lsquare mandrel in said sleeve having supporting projection on each face, a segmental cylindrical bar on eachf face sup-` portedfon projections andfformingv 'al cylinder therewith, pivotal arms onffsaid bars 'swingable' radially outward, cutting elements on said arms,

and means lfor retainingsaid arms inv position at,l

thevend of the sleeve when the mandrel is moved downwardly thereinto swingand lock said arms `invcuttingposition,I said bars 'being of different length' to 'support the arms centrally of the tool when thev mandrel'l is moved from the sleeve;

- CLINTON L. WALKER. 

